Optoelectronic component

ABSTRACT

An optoelectronic component includes a layer structure including an active zone that generates electromagnetic radiation, wherein the active zone is arranged in a plane, the layer structure includes a top side and four side faces, the first and third side faces are arranged opposite one another, the second and fourth side faces are arranged opposite one another, a strip-type ridge structure is arranged on the top side of the layer structure, the ridge structure extends between the first side face and the third side face, the first side face constitutes an emission face for electromagnetic radiation, a first recess is introduced into the top side of the layer structure laterally alongside the ridge structure, a second recess is introduced into the first recess, and the second recess extends as far as the second side face.

TECHNICAL FIELD

This disclosure relates to an optoelectronic component.

BACKGROUND

Optoelectronic components, for example, in the form of laser diodes areknown. US 2009/0137098 A1 and U.S. Pat. No. 7,724,793 B2 disclose alayer structure comprising an active zone that generates electromagneticradiation. A ridge structure is arranged on the layer structure, theridge structure being arranged between two side faces arranged parallelto one another.

There is nonetheless a need to provide an improved optoelectroniccomponent.

SUMMARY

We provide an optoelectronic component including a layer structureincluding an active zone that generates electromagnetic radiation,wherein the active zone is arranged in a plane, the layer structureincludes a top side and four side faces, the first and third side facesare arranged opposite one another, the second and fourth side faces arearranged opposite one another, a strip-type ridge structure is arrangedon the top side of the layer structure, the ridge structure extendsbetween the first side face and the third side face, the first side faceconstitutes an emission face for electromagnetic radiation, a firstrecess is introduced into the top side of the layer structure laterallyalongside the ridge structure, a second recess is introduced into thefirst recess, the second recess extends as far as the second side face,the first recess extends over an entire length of the laser diode fromthe first side face as far as the third side face along the second sideface, the first recess extends as far as the second side face, thesecond recess is introduced into a first base face of the first recess,the second recess extends along the second side face, the second recessis configured at a distance from the first side face and at a distancefrom the third side face, and the second recess leads into the secondside face.

We also provide an optoelectronic component including a layer structureincluding an active zone that generates electromagnetic radiation,wherein the active zone is arranged in a plane, the layer structureincludes a top side and four side faces, the first and third side facesare arranged opposite one another, the second and fourth side faces arearranged opposite one another, a strip-type ridge structure is arrangedon the top side of the layer structure, the ridge structure extendsbetween the first side face and the third side face, the first side faceconstitutes an emission face for electromagnetic radiation, a firstrecess is introduced into the top side of the layer structure laterallyalongside the ridge structure, a second recess is introduced into thefirst recess, the second recess extends as far as the second side face,the first recess extends over an entire length of the laser diode fromthe first side face as far as the third side face along the second sideface, in the region of the first recess, the second side face includeslaterally recessed wall faces, the second recess is introduced laterallyinto the first recess and into the recessed wall faces of the secondside face, the second recess is introduced into the top side of thelayer structure, the second recess extends along the second side face,and the second recess is configured at a distance from the first sideface and at a distance from the third side face.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic perspective illustration of an optoelectroniccomponent.

FIG. 2 shows a cross section through a laser diode including tworecesses.

FIG. 3 shows a cross section through a laser diode including threerecesses.

FIG. 4 shows a schematic plan view of a top side of the laser diode.

FIG. 5 shows a schematic cross section through a laser diode including achamfered recess.

FIG. 6 shows a schematic cross section through a further example of alaser diode including a recess which is configured partlyperpendicularly and partly in a chamfered fashion.

FIG. 7 shows a schematic cross section through a further example of alaser diode including a plurality of third recesses.

FIG. 8 shows a cross section through a further example of a laser diodeincluding a partly perpendicular and partly chamfered sidewall.

FIG. 9 shows a schematic perspective illustration of a further exampleof a laser diode including a recess at the second sidewall.

FIG. 10 shows a schematic perspective illustration of a further exampleof a laser diode including a recess on the third side face.

FIG. 11 shows a schematic perspective illustration of a laser diodeincluding a recess on the third side face and on the first side face.

FIG. 12 shows a schematic plan view of a part of a wafer includingcomponents according to FIG. 9 before the components are singulated.

FIG. 13 shows a schematic plan view of a part of a wafer with a furtherexample of components before the components are singulated.

FIG. 14 shows a schematic plan view of a part of a wafer includingcomponents according to FIG. 10 before the components are singulated.

FIG. 15 shows a schematic plan view of a part of a wafer includingcomponents according to FIG. 11 before the components are singulated.

LIST OF REFERENCE SIGNS

-   1 Laser diode-   2 Layer structure-   3 First side face-   4 Second side face-   5 Third side face-   6 Fourth side face-   7 Top side-   8 Ridge structure-   9 Active Zone-   10 Laser mode-   11 First recess-   12 Second recess-   13 First base face-   14 Second base face-   15 Breaking direction-   16 Third recess-   17 Third base face-   18 Wall face-   19 Angle-   20 Edge-   21 Upper section-   22 Lower section-   23 First wall face-   24 Second base face-   25 Second wall face-   26 Fourth recess-   27 Fifth recess-   28 Length-   31 Seventh recess-   32 Seventh base face-   33 Seventh wall face-   34 Further seventh wall face-   35 Distance-   36 Carrier-   37 Center plane-   40 Dislocation-   41 2^(nd) Dislocation-   42 3^(rd) Dislocation-   44 Passivation layer-   45 Wall face-   46 1^(st) Further wall face-   47 2^(nd) Further wall face-   48 3^(rd) Further wall face-   49 Depth-   50 Further sixth wall face-   51 Further sixth wall face-   52 First separating line-   53 Second separating line-   54 Wafer

DETAILED DESCRIPTION

Our optoelectronic component comprises a layer structure comprising anactive zone that generates electromagnetic radiation, wherein the layerstructure comprises a top side and four side faces, a strip-type ridgestructure is arranged on the top side of the layer structure, the ridgestructure extends between the first side face and the third side face,the first side face constitutes an emission face for electromagneticradiation, a first recess is introduced into the top side of the layerstructure laterally alongside the ridge structure, a second recess isintroduced into the first recess, and the second recess extends as faras the second side face. As a result, formation of dislocations in theevent of the breaking of the first and/or the third side face is largelyavoided. Moreover, in p-down mounting, a leakage current flowing via theside face is reduced.

The first recess may be introduced into the first side face and/or intothe third side face, wherein the second recess is introduced into thefirst side face and/or into the third side face. A further reduction information of dislocations in the event of the breaking of the firstand/or the third side face may be achieved as a result of thearrangement of the first and/or the third recess in the region of thefirst and/or the third side face.

At least one third recess may be introduced into a base face of thefirst recess laterally alongside the ridge structure. A furtherreduction in formation of dislocations in the event of the breaking ofthe first and/or the third side face may be achieved as a result.

The third recess may be introduced into the first and/or into the thirdside face. A further reduction in formation of dislocations in the eventof the breaking of the first and/or the third side face is achieved as aresult.

The third recess may be arranged substantially parallel to the secondside face, wherein the third recess is arranged at a distance from thefirst side face and at a distance from the third side face.

The first recess may extend along a longitudinal direction of the secondside face, wherein the first recess is arranged at a distance from thefirst side face and at a distance from the third side face.

The first recess may extend over a range of 1% to 99% of a longitudinalside of the second side face. A further reduction in leakage currentsflowing via the second side face in p-down mounting is achieved in thisway.

The second recess may extend along a longitudinal direction of thesecond side face, wherein the second recess is arranged at a distancefrom the first side face and at a distance from the third side face.

The second recess may extend over a range of 1% to 99%, in particular of50% to 95%, of a longitudinal side of the first side face. A furtherreduction in leakage currents flowing via the second side face in p-downmounting is achieved in this way.

The second recess may comprise a greater depth relative to a base faceof the first recess than the third recess.

The second recess may comprise a depth of 0.5 μm to 50 μm, in particular1 μm to 10 μm, relative to the top side. A sufficient reduction inleakage currents flowing via the second side face in p-down mounting isreduced in this way.

The second recess may comprise a depth of 2 μm to 6 μm relative to thetop side.

The second and fourth side faces may be configured mirror-symmetricallywith respect to a center plane, wherein the top sides arranged onopposite sides relative to the ridge structure are configuredmirror-symmetrically with respect to the center plane. Leakage currentsvia the second and third side faces are thus reduced. Furthermore,formation of dislocations at the first and/or at the third side face isreduced further.

At least walls and/or base faces of the first recess and/or of thesecond recess and/or of the third recess may be covered with apassivation layer. Leakage currents via the side faces may be reduced asa result.

The first recess may extend over an entire length of the laser diodefrom the first as far as the third side face along the second side face,wherein the first recess extends as far as the second side face, thesecond recess is introduced into a first base face of the first recess,the second recess extends along the second side face, the second recessis configured at a distance from the first side face and at a distancefrom the third side face, and the second recess leads into the secondside face.

The first recess may extend over an entire length of the laser diodefrom the first as far as the third side face along the second side face,wherein in the region of the first recess the second side face compriseslaterally recessed wall faces, the second recess is introduced laterallyinto the first recess and into the recessed wall faces, the secondrecess is introduced into the top side of the layer structure, thesecond recess extends along the second side face, and the second recessis configured at a distance from the first side face and at a distancefrom the third side face.

A further recess may be introduced into the first side face and into thetop side of the layer structure, wherein the further recess is arrangedbetween the ridge structure and the recessed wall face of the secondside face.

The further recess may comprise a base face, wherein the base face isarranged between the top side of the layer structure and a level of thesecond base face of the second recess.

A second further recess may be introduced into the third side face andinto the top side of the layer structure, wherein the second furtherrecess is arranged between the ridge structure and the recessed wallface of the second side face.

The second further recess may comprise a base face, wherein the baseface is arranged between the top side of the layer structure and a levelof the second base face of the second recess.

The second base face of the second recess may be arranged at the samelevel as a base face of the first recess.

The above-described properties, features and advantages and the way inwhich they are achieved will become clearer and more clearly understoodin association with the following description of the examples explainedin greater detail in association with the drawings.

FIG. 1 shows, in a schematic illustration, an optoelectronic componentin the form of a laser diode 1 comprising a layer structure 2. The layerstructure 2 comprises four side faces 3, 4, 5, 6. In general, the firstside face 3 and the third side face 5 are arranged parallel to oneanother. Likewise, in general, the second side face 4 and the fourthside face 6 are arranged parallel to one another. A strip-type ridgestructure 8 is arranged on a top side 7 of the layer structure 2. Theridge structure 8 extends in a longitudinal direction between the firstand third side faces 3, 5. At the first side face 3, an emission face 7is provided below the ridge structure 8, via which emission faceelectromagnetic radiation is emitted on the first side face 3.

In a coordinate system comprising an x-axis, a y-axis and a z-axis,which are each perpendicular to one another, the first and third sidefaces 3, 5 are arranged perpendicularly to the z-axis. The second andfourth side faces 4, 6 are arranged perpendicularly to the x-axis. Thetop side 7 is arranged perpendicularly to the y-axis. In the exampleillustrated, the ridge structure 8 is arranged centrally with respect toa width along the x-axis of the top side 7. The ridge structure coversonly a part of the width of the top side 7. The ridge structure 8extends along the z-axis perpendicularly to the first side face 3 fromthe first side face 3 as far as the third side face 5. Depending on theexample chosen, the ridge structure 8 may also end before the plane ofthe first and/or the third side face 3, 5 or be aligned at an angle ofnot equal to 90° with respect to the plane of the first and/or the thirdside face 3, 5. The first and third side faces may comprise mirrorlayers. Moreover, an insulation layer may be arranged on the top side 7.

The optoelectronic component is configured, for example, as an edgeemitting laser diode or as a light-emitting diode (LED). In particular,the laser diode/LED may be produced from a III-V semiconductor material,in particular from indium gallium nitride. The layer structure 2comprises an active zone 9, which is arranged perpendicularly to they-axis in a plane and may extend laterally along the x-axis beyond thewidth of the ridge structure. On account of the ridge structure 8, aguidance of a generated laser mode 10 below the ridge structure 8 in theactive zone 9 is achieved. The layer structure 2 may consist of a III-Vsemiconductor material and be arranged on a carrier. The substrateand/or the layer structure 2 may be based on a III-V compoundsemiconductor or a II-VI compound semiconductor or zinc oxide. The II-VIcompound semiconductor may be a sulfide or a selenide. The III-Vcompound semiconductor may be based on a nitride compound semiconductor,a phosphide compound semiconductor, an antimonite compound semiconductoror an arsenide compound semiconductor. The III-V compound semiconductormay be, for example, a nitride such as for instance, gallium nitride,indium nitride or aluminum nitride, a phosphide such as for instance,gallium phosphide or indium phosphide a first arsenide such as forinstance, gallium arsenide or indium arsenide. In this case, by way ofexample, the material system Al_(n)In_(1-n-m)Ga_(m)N may be provided,wherein 0≤n≤1, 0≤m≤1 and n+m≤1. Moreover, the material system maycomprise Al_(n)Ga_(m)In_(1-n-m)P, wherein 0≤n≤1, 0≤m≤1 and n+m≤1.Moreover, the material system may comprise Al_(n)Ga_(m)In_(1-n-m)Sb,wherein 0≤n≤1, 0≤m≤1 and n+m≤1.

During production of the laser diode 1, individual laser diodes 1 aredetached from an assemblage, in particular from a wafer, wherein inparticular the first and third side faces 3, 5 are produced with the aidof a process of breaking the wafer. The first and third side faces 3, 5should satisfy conditions stipulated for a good quality of the laserdiode 1, in particular constitute a planar face without disturbances anddislocations. Therefore, breaking the first and third side faces 3, 5 isan important process for the quality of the laser diode 1.

Hereinafter, various structures are presented which make possible aprocess of breaking the first and third side faces 3, 5, wherein a highquality of the first and third side faces 3, 5 is produced.

FIG. 2 shows a schematic partial cross section through an arrangementcomprising a first example of a laser diode 1 in the X-Y plane, which issecured to a carrier 36 by the ridge structure 8 using p-down mounting.The carrier 36 may be configured in the form of a semiconductorsubstrate. The active zone 9 is arranged in the layer structure 2,wherein with the aid of the ridge structure 8, during operation of thelaser diode 1, a laser mode 10 are generated below the ridge structure8. The laser mode 10 is reflected by the third side face 5 and is atleast partly emitted via the first side face 3.

The layer structure 2 comprises a first recess 11 between the ridgestructure 8 and the second side face 4 in the top side 7, the firstrecess extending in the x-axis in the direction of the second side face4 as far as a second recess 12. The first recess 11 comprises a firstbase face 13 and extends in the longitudinal direction, that is to sayalong the z-axis, for example, from the first side face 3 as far as thethird side face 5. The first recess 11 may also extend only over a partof the length of the component.

The first base face 13 and side faces 45 of the first recess 11 may beprovided with an electrically insulating passivation layer 44. Thepassivation layer 44 is configured as an oxide layer, for example, andmay be produced before the laser diodes are singulated, for example, inan oxidation method using oxygen plasma or water vapor at elevatedtemperatures. The first base face 13 and the side face 45 of the firstrecess 11 are constructed from silicon, for example, such that thepassivation layer may be formed from silicon oxide. Moreover, thepassivation layer may also be formed from SiN_(x), TiO₂ or Ta₂O₅.

The second recess 12 extends from the first base face 13 of the firstrecess 11 via a wall face 18 along the y-axis as far as a second baseface 14. The wall face 18 and the second base face 14 may likewise becovered by the passivation layer 44. The second recess 12 may extend inthe z-axis from the first side face 3 as far as the third side face 5.Moreover, the second recess 12 may extend along the z-axis only over apart of the length of the laser diode.

The first base face 13 is arranged along the y-axis, for example, in theregion of the plane in which the active zone 9 is arranged. In the eventof breaking, the layer structure 2 configured as a semiconductor layerstructure is broken in a breaking direction 15 from left to rightperpendicularly to the z-axis. On account of the first and secondrecesses 11, 12 in this case transverse facets and/or disturbances atthe first side face 3 are avoided or diverted into a region below thelaser mode 10. Moreover, the second and/or the fourth side face 4, 6 maylikewise be produced by breaking methods or sawing methods or etchingmethods.

A dislocation 40 is illustrated schematically, the dislocationproceeding from the wall face 18 of the second recess 12 and extendingalong the x-axis transversely over the width of the laser diode 1.However, the dislocation 40 is arranged below the laser mode 10 and thuscannot impair the quality of the electromagnetic radiation emitted bythe laser diode 1.

The top side 7 may be configured mirror-symmetrically with respect to acenter plane 37 on both sides of the ridge structure 8. The center plane37 is arranged parallel to the y-z plane and centrally in thex-direction in the ridge structure 8. The fourth side face 6 maylikewise be configured mirror-symmetrically with respect to the centerplane 37. Consequently, the fourth side face 6 is provided withcorresponding recesses 11, 12 in accordance with the second side face 4.

FIG. 3 shows a schematic partial cross section of a further example of alaser diode 1 in the x-y plane, wherein a third recess 16 is provided inaddition to the first and second recesses 11, 12. The third recess 16 isintroduced into the base face 13 of the first recess 11 along the x-axisbetween the ridge structure 8 and the second recess 12. The third recess16 may comprise a smaller depth than the second recess 12. Likewise, athird base face 17 of the third recess 16 may be arranged at least inthe region of the plane of the active zone 9 or below the plane of theactive zone 9. The third recess 16 may extend over the entire length inthe z-direction of the laser diode 1 or only over a partial section.Moreover, side faces and the third base face 17 of the third recess 16may be covered with a passivation layer 44. With the aid of the thirdrecess 16, a further improvement in the quality of the first side face 3may be achieved in the event of the breaking of the layer structure 2 inthe breaking direction 15 from left to right.

With the aid of the third recess 16, transverse facets or disturbanceswhich arise in a deeper region and are produced during breaking maylikewise be curbed. A dislocation 40 is illustrated schematically, thedislocation proceeding from the second recess 12 and extending along thex-axis transversely over the width of the laser diode. However, thedislocation 40 is arranged below the laser mode 10 and thus cannotimpair the quality of the laser radiation. Moreover, a seconddislocation 41 is illustrated, which proceeds from the second recess 12and extends along the x-axis transversely as far as the third recess 16.The third recess 16 prevents the further formation of the seconddislocation 41 in the direction of a region of the laser mode 10.

The first, second and/or third recess 11, 12, 16 may be arranged only inthe region of the first and third side faces 3, 5 and may not extendover the entire length of the laser diode in the z-axis. In a furtherexample, the first, the second and/or the third recess 11, 12, 16,depending on the example chosen, may be arranged in the region of thefirst and third side faces 3, 5 and may extend over the entire length ofthe laser diode 1 along the z-axis. In a further example, the first, thesecond and/or the third recess 11, 12, 16 may be arranged only in theregion of the first and third side faces 3, 5.

FIG. 4 shows a view of the example from FIG. 3 in a schematic view fromabove, wherein the first, second and third recesses 11, 12, 16 areconfigured in a manner only adjoining the first and third side faces 3,5. The first, second and third recesses 11, 12, 16 may also extend overthe entire length along the z-axis of the layer structure 2. The topside 7 and the second and fourth side faces 4, 6 are configuredmirror-symmetrically with respect to the center plane 37. Thepassivation layer is not explicitly illustrated.

FIG. 5 shows a schematic partial cross section in the x-y plane througha further example of a laser diode 1, wherein, in a manner adjoining thesecond side face 4, a second recess 12 is introduced into the top side 7of the layer structure 2. The second recess 12 comprises a wall face 18arranged at an inclination. The wall face 18 may be aligned at an angle19 of between 91° and 179° relative to the y-axis. In particular, thewall face 18 may be arranged at an angle 19 with respect to the y-axisof 135° to 155°. The second recess 12 may have a depth of 0.5 to 50 μmrelative to the top side 7. In particular, the depth of the recess 12may be 1 to 10 μm, in particular 2 to 6 μm. In this example of thesecond recess 12, the depth is considered to be a level of an edge 20 onthe y-axis at which the wall face 18 transitions into the second sideface 4. The edge 20 is aligned along the z-axis. Since dislocations 40preferably proceed perpendicularly to faces, it is possible to divertdisturbances and transverse facets downward by a chamfered second sideface 4, as illustrated schematically. The top side 7 and the wall face18 may be covered with a passivation layer 44. Moreover, the fourth sideface 6 of the laser diode 1 may be configured mirror-symmetrically withrespect to the second side face 4 in relation to the center plane 37.

FIG. 6 shows a partial cross section through a further example of alaser diode 1 in the y-x plane comprising a second recess 12, whichcomprises a first wall face 23 at the second side face 4 in an uppersection 21, the first wall face being arranged parallel to the y-axis.The first wall face 23 transitions into a second base face 14. Thesecond base face 14 does not extend as far as the second side face 4 inthe x-axis, but rather transitions into a second wall face 25 in a lowersection 22.

The second wall face 25 is configured in the form of an inclined facethat is at an angle 19 relative to the y-axis that may be 91° to 179°,in particular 135° to 155°. Consequently, in this example, a lowersection 22 of the second recess 12 is arranged at an inclination withrespect to the y-axis. Consequently, dislocations 40 or transversefacets produced in the lower region, in particular, may be diverted intodeeper regions. The top side 7 and/or the first wall face and/or thesecond wall face and/or the second base face 14 may be covered with apassivation layer 44. Moreover, the fourth side face 6 of the laserdiode 1 may be configured mirror-symmetrically with respect to thesecond side face 4 in relation to the center plane 37.

FIG. 7 shows a partial cross section through a further example of alaser diode 1 in the y-x plane that substantially corresponds to theexample from FIG. 3, wherein, however, a fourth and a fifth recess 26,27 are additionally introduced into the first base face 13 of the firstrecess 11. The fifth recess 27 may be dispensed with or a plurality ofrecesses may also be provided. The fourth and fifth recesses 26, 27 maybe configured in accordance with the third recess 16. Providing thefourth and fifth recesses 26, 27 makes it possible to curb furthertransverse facets 41 arising between the third recess 16 and the fourthrecess and/or between the fourth and fifth recesses 26, 27. The depthsof the third recess 16 and of the fourth and fifth recesses 26, 27 maybe different. Moreover, the wall faces of the third recess 16 and of thefourth and fifth recesses 26, 27 may also be arranged at an inclinationwith respect to the y-axis, as was explained on the basis of theexamples in FIGS. 5 and 6.

The top side 7 and/or the wall face 18 of the second recess 12 and/orthe second base face 14 of the second recess 12 and/or the walls andbase faces of the third and/or the fourth and/or the fifth recess 16,26, 27 may be covered with a passivation layer 44. Moreover, the fourthside face 6 of the laser diode 1 may be configured mirror-symmetricallywith respect to the second side face 4 relative to the center plane 37.Furthermore, the top side 7 arranged between the ridge structure 8 andthe fourth side face 6 may also comprise a third, a fourth and a fifthrecess and may be configured mirror-symmetrically with respect to thecenter plane 37.

FIG. 8 shows a partial cross section through a further example of alaser diode 1 in the y-x plane comprising a second recess 12. The secondrecess 12 comprises a first wall face 23 in an upper section 21, thefirst wall face being arranged at an angle 19 at an inclination withrespect to the y-axis. The angle 19 may be 91° to 179°, in particular135° to 155°. The first wall face 23 transitions via an edge 20 into alower section 22 and a second wall face 25. The edge 20 is made parallelto the z-axis in particular over the entire length of the laser diode 1.The second wall face 25 is arranged parallel to the y-axis. The secondwall face 25 transitions via a second base face 14 into the second sideface 4 in the direction of the x-axis. Consequently, in this example, bythe first wall face 23 arranged at an inclination, disturbances andtransverse facets 40 that may arise during breaking are diverteddownward outside the region of the laser mode 10. The top side 7 and/orthe first and/or the second wall face 23, 25 and/or the second base face14 of the second recess 12 may be covered with a passivation layer 44.Moreover, the fourth side face 6 of the laser diode 1 may be configuredmirror-symmetrically with respect to the second side face 4 relative tothe center plane 37.

FIG. 9 shows, in a schematic perspective illustration, a partial sectionof a further example of a laser diode 1 with a view of the first sideface 3, wherein a first recess 11 comprising a first base face 13 isconfigured in the top side 7. The first recess 11 extends in thez-direction, for example, over the entire length of the laser diode 1 oronly over a part of the entire length of the laser diode 1.Consequently, the first recess 11 may be configured in the form of astepped gradation. The first recess 11 comprises a first wall face 45and a first base face 13. The first wall face 45 may be arrangedperpendicularly to the top side 7. The first base face 13 may bearranged parallel to the top side 7. The wall face 45 and/or the firstbase face 13 may be covered with a passivation layer 44.

A second recess 12 is introduced into the first base face 13 of thefirst recess 11. The second recess 12 extends in the x-direction as faras the second side face 4. Consequently, the second recess 12 is openedin the first base face 13 and in the second side face 4. The secondrecess 12 comprises three further wall faces 46, 47, 48 and a secondbase face 14. The second base face 14 is arranged, e.g., parallel to thefirst base face 13. The first wall face 46 is arranged in a manneroffset inward relative to the third side face 5. The first wall face 46may be arranged parallel to the third side face 5. The third wall face48 is arranged in a manner offset inward relative to the first side face3. The third wall face 48 may be arranged parallel to the first sideface 3. The three further wall faces 46, 47, 48 and the second base face14 may be covered with a thin passivation layer 44, which changes theshape of the second recess 12 only insignificantly. The second recess 12is arranged between the first and third side faces 3, 5 and at adistance from the first and third side faces 3, 5 in the exampleillustrated. The first and third side faces 3, 5 constitute facet faces.

The second recess 12 may also extend as far as the first and third sidefaces 3, 5 and may be configured in the form of a second steppedgradation. Moreover, the second recess 12 may also be arranged only inthe region of the first and third side faces 3, 5. In this example, thefirst recess 11, proceeding from the top side 7, comprises a depthparallel to the Y-axis of 0.5 to 25 μm. The second recess 12 comprises adepth 49 with respect to the first base face 13 of the first recess 11which is in the range of 0.5 μm to 50 μm, for example, 1 μm to 10 μm, inparticular 2 μm to 6 μm. The first base face 13 may be arranged above orbelow the active zone 9.

The length 28 of the second recess 12 parallel to the z-axis may extend5% to 100% of the entire length of the laser diode 1 parallel to thez-axis. In the case of a length of 100%, the second recess 12 comprisesonly one second further wall face 47 and a second base face 14. Inparticular, the length 28 of the second recess may extend 50% to 99% ofthe length of the laser diode 1 parallel to the z-axis. Moreover, thelength 28 of the second recess 12 may extend 80% to 97% along the z-axisof the laser diode. The second recess 12 may be arranged symmetricallyand centrally with respect to the length of the laser diode in thez-direction. With the aid of these examples, it is possible to reduceleakage currents in the case of p-down mounting, in which the ridgestructure 8 is mounted on a carrier, on account of the first and secondrecesses 11, 12 and/or the passivation layer 44. Moreover, dislocationsin the event of the breaking of the first and/or the third side face 3,5 are reduced as a result the recesses 11, 12. Moreover, the fourth sideface 6 of the laser diode 1 may be configured mirror-symmetrically withrespect to the second side face 4 relative to the center plane 37.

FIG. 10 shows a perspective partial illustration of a further example ofa laser diode 1 with a view of the first side face 3. A first recess 11is introduced into the top side 7, the first recess directly adjoiningthe second side face 4 and extending from the first side face as far asthe third side face 3, 5. The first recess 11 comprises a first baseface 13, which is arranged, e.g., parallel to the top side 7. Moreover,the first recess 11 is delimited by two further sixth wall faces 50, 51.The two further sixth wall faces 50, 51 additionally constitute inwardlyrecessed parts of the second side face 4. Consequently, the first recess11 forms a lateral stepped gradation of the first side face 4.

A second recess 12 is introduced into the top side 7 and into the firstrecess 11. A boundary between the first recess 11 and the second recess12 is illustrated in a dashed manner on the first base face 13.Moreover, the second recess 12 adjoins the further wall faces 50, 51 ofthe second side face 4. The second recess 12 comprises three furtherwall faces 46, 47, 48 and a second base face 14. The second recess 12 isarranged between the first and third side faces 3, 5 and at a distancefrom the first and third side faces 3, 5. In this example, the firstrecess 11 and the second recess 12 comprise the same depth along theY-axis. The second recess 12 comprises a depth with respect to the topside 7 which is 0.5 μm to 50 μm, for example, 1 μm to 10 μm, inparticular 2 μm to 6 μm.

The length 28 of the second recess 12 parallel to the z-axis may extend5% to 100% of the entire length of the laser diode 1 parallel to thez-axis. The second recess 12 may be arranged centrally with respect tothe longitudinal extent of the laser diode 1. In a length of 100%, thesecond recess 12 comprises only one second further wall face 47 and asecond base face 14. In particular, the length 28 of the second recess12 may extend 50% to 99% of the length of the laser diode 1 parallel tothe z-axis. Moreover, the length 28 of the second recess 12 may extend80% to 97% along the z-axis of the laser diode. With the aid of theseexamples, it is possible to reduce leakage currents in the case ofp-down mounting, in which the ridge structure 8 is mounted on a carrier,on account of the first and second recesses 11, 12 and/or thepassivation layer 44. Moreover, dislocations in the event of thebreaking of the first and/or the third side face 3, 5 are reduced as aresult the recesses 11, 12. Moreover, the fourth side face 6 of thelaser diode 1 may be configured mirror-symmetrically with respect to thesecond side face 4 relative to the center plane 37 and may comprise acorresponding first and second recess 11, 12. The first and secondrecesses 11, 12 of the fourth side 6 may also comprise different shapesor dimensions than the first and second recesses 11, 12 of the secondside 4.

The three further wall faces 46, 47, 48 and the second base face 14 ofthe second recess 12 and the first base face 13 and the further sixthwall faces 50, 51 may be covered with a passivation layer 44.

An at least partly passivated second side face 4 having laterallydifferent widths, e.g., is thinner in the region of the first and thirdside faces, enables a combination with a deep mesa structure withadditional recesses in the region of the first and third side faces 3,5, even if the active zone 9 is situated very close to a side face ofthe layer structure and is, for example, at a distance of less than 50μm in an asymmetrical ridge position. As a result, it is possible toreduce leakage currents in p-down mounting, in which the ridge structure8 is mounted on a carrier. Moreover, transverse facets and/ordisturbances may be curbed. Moreover, the fourth side face 6 of thelaser diode 1 may be configured mirror-symmetrically with respect to thesecond side face 4 relative to the center plane 37.

FIG. 11 shows a partial illustration of one example of a laser diode 1with a view of the first side face 3, which substantially corresponds tothe example from FIG. 10. In this case, however, a seventh recess 31 isadditionally provided, which is introduced into the top side 7 of thelayer structure 2 in the region of the first side face 3. The seventhrecess 31 comprises a seventh base face 32. The seventh base face 32 isarranged between the top side 7 and the second base face 14 of thesecond recess 12. Moreover, the seventh recess 31 extends in the x-axisright into a region in which the second recess 12 is also formed in anoffset manner laterally in the z-axis. The seventh recess 31additionally affords the possibility of curbing transverse facets anddisturbances in the event of the breaking of the laser diode 1 or in theevent of the breaking of the first side face 3. A seventh recess 31 asin the first side face 3 may also be arranged on the third side face 5.

The second recess 12 with the wall face 18 is at a distance from theridge structure 8 which is the same or smaller or larger compared to theseventh recess 31 with a seventh wall face 33 facing the ridge structure8 or is aligned parallel to the z-axis. Moreover, the seventh recess 31comprises a further seventh wall face 34 situated opposite the seventhwall face 33. The further seventh wall face 34 is at a greater distancefrom the ridge structure 8 than the wall face 18 of the second recess12. The second and seventh recesses 12, 31 are at a distance 35 from oneanother in the z-direction. The faces of the seventh recess 31 may becovered with a passivation layer 44.

On the top side 7 of the laser diode 1, an insulation layer is appliedon both sides of the ridge structure 8 such that a current flow to theregion of the ridge structure 8 is limited. Moreover, the second andfourth side faces 4, 6 and also the recesses are covered with apassivation layer 44. The three further wall faces 46, 47, 48 and thesecond base face 14 of the second recess 12 and the first base face 13and the further sixth wall faces 50, 51 may be covered with apassivation layer 44. The passivation layer 44 is produced, e.g., withthe aid of a chemical conversion, in particular by an oxidation of thematerial of the side faces. The side faces 4, 6 are composed of silicon,for example, wherein the passivation layer consists of silicon oxide.

FIG. 12 shows a schematic plan view of a part of a wafer 54 comprisingcomponents in accordance with FIG. 9 before the components aresingulated. In this case, first separating lines 52 and secondseparating lines 53 are illustrated as dashed lines. The firstseparating lines 52 run parallel to the strip-type ridge structures 8.The second separating lines 53 run perpendicularly to the ridgestructures 8.

The first recesses 11 are configured as parallel strips. The secondrecesses 12 are configured as strips arranged in parallel lines. Firstseparating lines 52 and second separating lines 53 are illustrated asdashed lines. The first separating lines 52 run parallel to thestrip-type ridge structures 8 through the middle of the first and secondrecesses 11, 12. The second separating lines 53 each run perpendicularlyto the ridge structures 8 between two second recesses 12. The secondseparating lines 53 define the first and third side faces of acomponent. The first separating lines 52 define the second and fourthside faces of the components. The components are singulated inaccordance with the separating lines 52, 53. In this case, the wafer 54is broken along the second separating lines 53. The wafer 54 maylikewise be broken along the first separating lines 52. In the exampleillustrated, the first recess 11 extends over an entire length of acomponent. The second recess 12 extends only over a part of the lengthof a component.

FIG. 13 shows a schematic plan view of a part of a wafer 54 comprising afurther example of components before the components are singulated. Inthis case, first separating lines 52 and second separating lines 53 areillustrated as dashed lines. The first separating lines 52 run parallelto the strip-type ridge structures 8. The second separating lines 53 runperpendicularly to the ridge structures 8.

The first recesses 11 are configured as parallel strips. The secondrecesses 12 are configured as parallel strips. First separating lines 52and second separating lines 53 are illustrated as dashed lines. Thefirst separating lines 52 run parallel to the strip-type ridgestructures 8 through the middle of the second recesses 12. The secondseparating lines 53 each run perpendicularly to the ridge structures 8between two second recesses 12.

The second separating lines 53 define the first and third side faces ofa component. The first separating lines 52 define the second and fourthside faces of the components. The components are singulated inaccordance with the separating lines 52, 53. In this case, the wafer 54is broken along the second separating lines 53. The wafer 54 maylikewise be broken along the first separating lines 52. The componentsare configured substantially in accordance with FIG. 12, wherein in thisexample, however, the second recesses 12 extend over the entire lengthof the components.

FIG. 14 shows a schematic plan view of a part of a wafer 54 comprisingcomponents in accordance with FIG. 10 before the components aresingulated. The ridge structures 8 are arranged parallel to one another.

The first recesses 11 are configured as parallel strips. The secondrecesses 12 are configured as strips arranged in parallel lines. Firstseparating lines 52 and second separating lines 53 are illustrated asdashed lines. The first separating lines 52 run parallel to thestrip-type ridge structures 8 through the middle of the first recesses11. The second separating lines 53 run perpendicularly to the ridgestructures 8 in each case between two second recesses 12.

The second separating lines 53 define the first and third side faces ofa component. The first separating lines 52 define the second and fourthside faces of the components. The components are singulated inaccordance with the separating lines 52, 53. In this case, the wafer 54is broken along the second separating lines 53. The wafer 54 maylikewise be broken along the first separating lines 52. The firstrecesses 11 extend over the entire length of the components. The secondrecesses 12 extend only over a part of the length of the components.

FIG. 15 shows a schematic plan view of a part of a wafer 54 comprisingcomponents in accordance with FIG. 11 before the components aresingulated. The arrangement is as in FIG. 14, wherein seventh recesses31 are additionally provided as well. The ridge structures 8 arearranged parallel to one another. In this case, first separating lines52 and second separating lines 53 are illustrated as dashed lines. Thefirst recesses 11 are configured as parallel strips. The second recesses12 are configured as strips arranged in parallel lines. First separatinglines 52 and second separating lines 53 are illustrated as dashed lines.The first separating lines 52 run parallel to the strip-type ridgestructures 8 through the middle of the first recesses 11. The secondseparating lines 53 run perpendicularly to the ridge structures 8 ineach case between two second recesses 12 and centrally through seventhrecesses 31.

The second separating lines 53 define the first and third side faces ofa component. The first separating lines 52 define the second and fourthside faces of the components. The components are singulated inaccordance with the separating lines 52, 53. In this case, the wafer 54is broken along the second separating lines 53. The wafer 54 maylikewise be broken along the first separating lines 52. The seventhrecesses 31 are arranged on the second separating lines 53.

Although our components have been more specifically illustrated anddescribed in detail by preferred examples, this disclosure is notrestricted by the examples disclosed and other variations may be derivedtherefrom by those skilled in the art, without departing from the scopeof protection of the appended claims.

This application claims priority of DE 10 2015 116 712.3, the subjectmatter of which is incorporated herein by reference.

The invention claimed is:
 1. An optoelectronic component comprising alayer structure comprising an active zone that generates electromagneticradiation, wherein the active zone is arranged in a plane, the layerstructure comprises a top side and four side faces, the first and thirdside faces are arranged opposite one another, the second and fourth sidefaces are arranged opposite one another, a strip-type ridge structure isarranged on the top side of the layer structure, the ridge structureextends between the first side face and the third side face, the firstside face constitutes an emission face for electromagnetic radiation, afirst recess is introduced into the top side of the layer structurelaterally alongside the ridge structure, a second recess is introducedinto the first recess, the second recess extends as far as the secondside face, the first recess extends over an entire length of the laserdiode from the first side face as far as the third side face along thesecond side face, in the region of the first recess, the second sideface comprises laterally recessed wall faces, the second recess isintroduced laterally into the first recess and into the recessed wallfaces of the second side face, the second recess is introduced into thetop side of the layer structure, the second recess extends along thesecond side face, and the second recess is configured at a distance fromthe first side face and at a distance from the third side face.
 2. Thecomponent according to claim 1, wherein a further recess is introducedinto the first side face and into the top side of the layer structure,and the further recess is arranged between the ridge structure and therecessed wall face of the second side face.
 3. The component accordingto claim 2, wherein the further recess comprises a base face, and thebase face is arranged between the top side and a level of the secondbase face of the second recess.
 4. The component according to claim 2,wherein a second further recess is introduced into the third side faceand into the top side of the layer structure, and the further recess isarranged between the ridge structure and the recessed wall face.
 5. Thecomponent according to claim 4, wherein the second further recesscomprises a base face, and the base face is arranged between the topside of the layer structure and a level of the second base face of thesecond recess.
 6. The component according to claim 1, wherein a secondbase face of the second recess is arranged at the same level as a firstbase face of the first recess.
 7. The component according to claim 1,wherein the second recess extends over 1% to 99% of a longitudinal sideof a second side face.
 8. The component according to claim 1, whereinthe second recess comprises a depth of 0.5 μm to 50 μm relative to thetop side.
 9. The component according to claim 8, wherein the secondrecess comprises a depth of 2 μm to 6 μm relative to the top side. 10.The component according to claim 1, wherein the second side face and thefourth side face are configured on both sides with respect to a centerplane, and/or the top sides arranged on opposite sides relative to theridge structure are configured with respect to the center plane.
 11. Thecomponent according to claim 1, wherein the second recess comprises adepth of 1 μm to 10 μm relative to the top side.
 12. The componentaccording to claim 1, wherein the second side face and the fourth sideface are configured on both sides mirror-symmetrically with respect to acenter plane, and the top sides arranged on opposite sides relative tothe ridge structure are configured mirror-symmetrically with respect tothe center plane.
 13. The component according to claim 1, wherein thesecond recess adjoins further wall faces of the second side face, andthe second recess comprises three further wall faces and a second baseface.
 14. The component of claim 1, wherein the second recess adjoinsfurther wall faces of the second side face, the second recess comprisesthree further wall faces and a second base face, and the three furtherwall faces and the second base face of the second recess and the firstbase face and the further wall faces of the second side face are coveredwith a passivation layer.
 15. The component of claim 14, wherein the topside of the layer structure is covered by a passivation layer.
 16. Thecomponent of claim 1, wherein a further recess is introduced into thefirst side face and into the top side of the layer structure, thefurther recess is arranged between the ridge structure and the recessedwall face of the second side face, and the faces of the further recessare covered with a passivation layer.
 17. The component of claim 1,wherein the component is configured as an edge emitting laser diode oras a light-emitting diode, and the layer structure consists of a III-Vsemiconductor material and is arranged on a carrier.
 18. The componentof claim 1, wherein the component is configured as an edge emittinglaser diode or as a light-emitting diode, and the layer structure isbased on a III-V compound semiconductor or a II-VI compoundsemiconductor.
 19. The component of claim 1, wherein the component isconfigured as an edge emitting laser diode or as a light-emitting diode,and the layer structure is based on zinc oxide.
 20. The component ofclaim 1, wherein the layer structure is based onAl_(n)In_(1-n-m)Ga_(m)N, wherein 0≤n≤1, 0≤m≤1 and n+m≤1 orAl_(n)Ga_(m)In_(1-n-m)P, wherein 0≤n≤1, 0≤m≤1 and n+m≤1 orAl_(n)Ga_(m)In_(1-n-m)Sb, wherein 0≤n≤1, 0≤m≤1 and n+m≤1.